[Anonymouse]

Metal wears out too.
Anonymouse always took excellent care of spinning reels, taking them apart cleaning, and liberally re-coating the metal inner gear workings with petroleum jelly, several times per season.
Of course Anonymouse IS harder on reels than most fishermen, subjecting them to immersion quite often while wading - and sand is inevitable with the way Anonymouse bank fishes at times on the Wisconsin River and other locations. (Forked stick for a bank rod holder.)

Point here being, back in the 80s & 90s Anonymouse had a few Pfluegers and Shakespeares wear out in the crank hole of the body, even though they were waterproofed and had metal "O" bearings to carry the crank handle and through-rod (screw cap on the other side).
The fine grit sand eventually just wore away at the metal & the handles got wobbly due to hole wear enlargement.

Most fishermen probably won't ever have that happen, and Anonymouse still owns at least 1 Pflueger .035 from those days that is working just as well as it did when new.
But, metal isn't necessarily impervious to wear and failure any more than modern composites are.
It may be that composites actually are superior in this particular instance.
They are incredible hard materials, able to stand up to YEARS of abrasion, shock, and mishandling.

Don't get Anonymouse started on what happened to an Abu Garcia 6500C baitcasting reel spool when he used it to fly kites one spring.